<div class="input-field">
  <label {{#empty model.content}}{{else}}class="active"{{/empty}}>消息内容</label>
  <textarea name="content" class="materialize-textarea">{{model.content}}</textarea>
</div>
<div class="input-field">
  <label {{#empty model.keywords}}{{else}}class="active"{{/empty}}>关键词(逗号分割)</label>
  <textarea name="keywords" class="materialize-textarea">{{keywords}}</textarea>
</div>